Administration of antibiotics in combination. Determination of antibacterial effectivity of blood serum and urine after simultaneous administration of macrolides and tetracyclines.
The authors deal with antibacterial effectivity of blood serum and urine in simultaneous administration of macrolids and tetracyclines under in vivo conditions, using Staphylococcus aureus strains. The obtained results suggest that pharmacodynamic effect, i.e., higher effective concentration, is induced in some combinations of these preparations. It was found mainly after the administration of the combinations of erythromycin 250 mg + doxycycline 200 mg in all the chosen reference strains S. a. The results have also shown that the combination of erythromycin with tetracycline has a higher effect when an erythromycin-resistant strain is used than when using a strain resistant to tetracycline.